X-Git-Url: https://git.distorted.org.uk/~mdw/sod/blobdiff_plain/7dd104a3fdcd6f0094ec2e0f8c6a18564949eb49..82567ea97e4f9374e8a3d586ea49ad9bf3dff3dc:/doc/sod.sty

diff --git a/doc/sod.sty b/doc/sod.sty
index 45d623e..69b4d3d 100644
--- a/doc/sod.sty
+++ b/doc/sod.sty
@@ -25,9 +25,17 @@
 
 \ProvidesPackage{sod}
 
+%%%--------------------------------------------------------------------------
+%%% Basic style things.
+
 %% More reference types.
 \defxref{p}{part}
 
+%% A gadget to include in `\xref': call as
+%%
+%%      \xref[\instead{THING}]{LABEL}
+%%
+%% to replace the usual `section' or whatever with THING.
 \def\instead#1#2{#1}
 
 %% Other languages with special typesetting.
@@ -106,7 +114,7 @@
 %% conditionally.
 \def\@scripts{\futurelet\@ch\@scripts@i}
 \begingroup\lccode`\~=`\_\lowercase{\endgroup
-\def\@scripts@i{\if1\ifx\@ch~1\else\ifx\@ch^1\else0\fi\fi%
+\def\@scripts@i{\if1\ifx\@ch~1\else\ifx\@ch_1\else\ifx\@ch^1\else0\fi\fi\fi%
   \expandafter\@scripts@ii\else\expandafter\m@maybe@end\fi}}
 \def\@scripts@ii#1#2{\m@maybe#1{#2}\@scripts}
 
@@ -134,8 +142,13 @@
 \atdef ({\m@maybe(\@scripts}
 \atdef ){\m@maybe)\@scripts}
 \atdef !{\m@maybe|\@scripts}
+
 \def\returns{\m@maybe\longrightarrow\m@maybe@end\hspace{0.5em}\ignorespaces}
+\def\nlret{\\\hspace{4em}\returns}
 \atdef >{\leavevmode\unskip\hspace{0.5em}\returns}
+
+%% Extra syntax for common tokens.
+\atdef ~{\textasciitilde}
 \atdef -{\leavevmode\hbox\bgroup\futurelet\ch@\@dash}
 \def\@dash{%
   \ifx\ch@>%
@@ -158,18 +171,35 @@
 \def\@semicomment#1\\{\comment{#1}\\}
 \atdef ;{;\@semis;}
 
-%% Environment for setting programs.  Newlines are explicit, because
-%% otherwise I need comments in weird places to make the vertical spacing
-%% come out properly.  You can write `\obeylines' if you really want to.
+%% Put a chunk of text in a box.
+\newenvironment{boxy}[1][\q@]{%
+  \savenotes%
+  \dimen@\linewidth\advance\dimen@-1.2pt\advance\dimen@-2ex%
+  \medskip%
+  \vbox\bgroup\hrule\hbox\bgroup\vrule%
+  \vbox\bgroup\vskip1ex\hbox\bgroup\hskip1ex\minipage\dimen@%
+  \def\@temp{#1}\ifx\@temp\q@\else\leavevmode{\headfam\bfseries#1\quad}\fi%
+}{%
+  \endminipage\hskip1ex\egroup\vskip1ex\egroup%
+  \vrule\egroup\hrule\egroup%
+  \medskip%
+  \spewnotes%
+}
+
+%%%--------------------------------------------------------------------------
+%%% Environment for setting programs.
+
+%% Main guts of `prog' and `nprog'.
 \def\@prog{\let\prog@@cr\@tabcr\let\@tabcr\@progcr\codeface\tabbing}
-\def\prog{\quote\@prog}
-\def\endprog{\endtabbing\endquote}
-\let\nprog\@prog
-\let\endnprog\endtabbing
-\def\ind{\quad\=\+\kill}
+
+%% Newlines: called by `\\' within a `prog'.
+%%
+%% \\           newline without following break
+%% \\[SKIP]     newline /with/ break and vertical glue
+%% \\*[SKIP]    newline without break, with optional glue
+%% \\+          newline with break and a vertical gap
+%% \\-          newline without break, with a tiny gap
 \def\@progcr{\futurelet\@tempa\@progcr@i}
-{\def\:{\gdef\@progcr@sp}\: {\@progcr}}
-\atdef~{\textasciitilde}
 \def\@progcr@i{%
   \ifx\@tempa\@sptoken\let\next@\@progcr@sp\else
   \if1\ifx\@tempa[1\else
@@ -186,81 +216,87 @@
 \def\@progcr@ii#1{\csname @progcr@#1\endcsname\ignorespaces}
 \@namedef{@progcr@+}{\prog@@cr[\medskipamount]}
 \@namedef{@progcr@-}{\prog@@cr*[\jot]}
-\def\macsl{\`\textbackslash\hskip\leftmargin}
+{\def\:{\gdef\@progcr@sp}\: {\@progcr}} % \@progcr@sp eats space and recurses
 
-%% Put a chunk of text in a box.
-\newenvironment{boxy}[1][\q@]{%
-  \savenotes
-  \dimen@\linewidth\advance\dimen@-1.2pt\advance\dimen@-2ex%
-  \medskip%
-  \vbox\bgroup\hrule\hbox\bgroup\vrule%
-  \vbox\bgroup\vskip1ex\hbox\bgroup\hskip1ex\minipage\dimen@%
-  \def\@temp{#1}\ifx\@temp\q@\else\leavevmode{\headfam\bfseries#1\quad}\fi%
-}{%
-  \endminipage\hskip1ex\egroup\vskip1ex\egroup%
-  \vrule\egroup\hrule\egroup%
-  \medskip%
-  \spewnotes%
-}
+%% Set a program in `codeface', with implicit tabbing and other toys.
+%% Newlines are explicit, because otherwise I need comments in weird places
+%% to make the vertical spacing come out properly.  You can write
+%% `\obeylines' if you really want to.
+\def\prog{\quote\@prog}
+\def\endprog{\endtabbing\endquote}
+
+%% Like `prog', but without indenting the code.  Use this within environments
+%% which already set their contents out from the body text in some
+%% distinctive way.
+\let\nprog\@prog
+\let\endnprog\endtabbing
+
+%% Indent the following material.  Cancel using `\-'.
+\def\ind{\quad\=\+\kill}
+
+%% Show a backslash by the right-hand margin; for multiline macros etc.
+\def\macsl{\`\textbackslash\hskip\leftmargin}
 
-%% Lisp documentation machinery.
+%%%--------------------------------------------------------------------------
+%%% Machinery for describing functions, etc.
+
+%% \definedescribecategory{CAT}[KIND]{NAME}
+%%
+%% Define a category of things to document.  CAT is a short label identifying
+%% the category to `\describe', `\descref', and friends.  The NAME is the
+%% text to show in the description headline; it is a macro body which is
+%% passed an argument `#1' that applies a modifier to some portion of the
+%% text.
+%%
+%% The KIND allows additional arguments to be collected, included in label
+%% strings, and mentioned in the index.  The default is `plain'.
 \def\definedescribecategory#1{%
   \@ifnextchar[{\def@desc{#1}}{\def@desc{#1}[plain]}}
 \def\def@desc#1[#2]#3{\@namedef{cat!#1}##1{#3}\@namedef{catsw!#1}{#2}}
+
+%% \describecategoryname[MOD]{CAT}
+%%
+%% Typeset the category name for CAT, modified by MOD.
 \def\describecategoryname{\@ifnextchar[\@descname@i{\@descname@i[]}}
 \def\@descname@i[#1]#2{%
   \expandafter\let\expandafter\@tempa\csname cat!#2\endcsname%
   \expandafter\let\expandafter\@tempb\csname modcat/#1\endcsname%
   \ifx\@tempa\relax\@tempb{#2}\else\@tempa\@tempb\fi}
+
+%% Call a modifier method.
 \def\@mod@dispatch#1#2{\csname #1/#2\endcsname}
+
+%% Call a description method given the category.
 \def\@desc@dispatch#1#2{%
   \csname #1/%
-  \expandafter\ifx\csname catsw!#2\endcsname\relax plain%
-  \else \csname catsw!#2\endcsname \fi%
+    \expandafter\ifx\csname catsw!#2\endcsname\relax plain%
+    \else \csname catsw!#2\endcsname \fi%
   \endcsname%
 }
 
-\definedescribecategory{sym}{symbol}
-\definedescribecategory{fun}{#1{function}}
-\definedescribecategory{gf}{generic #1{function}}
-\definedescribecategory{msg}{message}
-\definedescribecategory{var}{variable}
-\definedescribecategory{modvar}{module variable}
-\definedescribecategory{const}{constant}
-\definedescribecategory{meth}[method]{primary #1{method}}
-\definedescribecategory{ar-meth}[method]{\code{:around} #1{method}}
-\definedescribecategory{be-meth}[method]{\code{:before} #1{method}}
-\definedescribecategory{af-meth}[method]{\code{:after} #1{method}}
-\definedescribecategory{cls}{class}
-\definedescribecategory{rst}{restart}
-\definedescribecategory{ty}{type}
-\definedescribecategory{type}{type}
-\definedescribecategory{mac}{#1{macro}}
-\definedescribecategory{feat}{feature macro}
-\definedescribecategory{lmac}{local #1{macro}}
-\definedescribecategory{parse}{parser spec}
-\definedescribecategory{parseform}{parser form}
-\definedescribecategory{opt}{option handler}
-\definedescribecategory{optmac}{option macro}
-\definedescribecategory{plug}{pluggable parser}
-\def\nlret{\\\hspace{4em}\returns}
-
+%% Modifier methods for the default empty modifier.
 \@namedef{modcat/}#1{#1}
 \@namedef{modlabel/}#1{#1}
 \@namedef{modindex/}#1{#1@\noexpand\code{#1}}
 
+%% Modifier methods for `setf'.  The name text prefixes the relevant word
+%% with `setf-'.
 \@namedef{modcat/setf}#1{\code{setf}-#1}
 \@namedef{modlabel/setf}#1{setf/#1}
 \@namedef{modindex/setf}#1{#1@\noexpand\code{#1}}
 
+%% Modifier methods for words with *earmuffs*.  Sort into the index without
+%% the earmuffs.
 \@namedef{modcat/muffs}#1{#1}
 \@namedef{modlabel/muffs}#1{*#1*}
 \@namedef{modindex/muffs}#1{#1@\noexpand\code{*#1*}}
 
+%% Modifier methods for :keywords.  Sort into the index without the `:'.
 \@namedef{modcat/kwd}#1{#1}
 \@namedef{modlabel/kwd}#1{:#1}
 \@namedef{modindex/kwd}#1{#1@\noexpand\code{:#1}}
 
+%% Category-kind methods for plain categories.
 \@namedef{descargs/plain}#1{#1{}}
 \@namedef{desclabel/plain}#1#2#3{#1:\@mod@dispatch{modlabel}{#2}{#3}}
 \@namedef{descindex/plain}#1#2#3{%
@@ -268,19 +304,10 @@
   \protect\describecategoryname[#2]{#1}%
 }
 
-\@namedef{descargs/method}#1#2{#1{{#2}}}
-\@namedef{desclabel/method}#1#2#3#4%
-  {#1:\@mod@dispatch{modlabel}{#2}{#3}(#4)}
-\@namedef{descindex/method}#1#2#3#4{%
-  \@mod@dispatch{modindex}{#2}{#3}!%
-  \protect\describecategoryname[#2]{#1}%
-  \protect\fmtspecs{ specialized at }{#4}%
-}
-
-\def\q@{\q@}
-\def\@setf{setf}
-
-\def\fmtspecs#1#2{%
+%% Category-kind methods for `method' categories.  Collect an extra argument
+%% listing the specializers: include them in the label, and typeset them in
+%% the index.
+\def\@fmtspecs#1#2{%
   \if!#2!\else\count@\z@\toks@{}#1\@fmtspecs@i#2,\q@,\fi}
 \def\@fmtspecs@i#1,{%
   \def\@tempa{#1}%
@@ -298,12 +325,28 @@
     \expandafter\@fmtspecs@i%
   \fi%
 }
+\@namedef{descargs/method}#1#2{#1{{#2}}}
+\@namedef{desclabel/method}#1#2#3#4%
+  {#1:\@mod@dispatch{modlabel}{#2}{#3}(#4)}
+\@namedef{descindex/method}#1#2#3#4{%
+  \@mod@dispatch{modindex}{#2}{#3}!%
+  \protect\describecategoryname[#2]{#1}%
+  \protect\@fmtspecs{ specialized at }{#4}%
+}
 
-%% \parse@dhd{NEXT}[MOD]{CAT}{...}...[NAME]{SYNOPSIS}
-%% call NEXT{MOD}{CAT}{{...}...}{NAME}{SYNOPSIS}
-%%            #1   #2      #3     #4      #5
+%% Some magic strings.
+\def\q@{\q@}
 \def\@setf{setf}
 \def\@starstar{**}
+
+%% \parse@dhd{NEXT}[MOD]{CAT}{...}...[NAME]{SYNOPSIS}
+%%
+%% Parse the arguments for a description header, and call
+%%
+%%      NEXT{MOD}{CAT}{{...}...}{NAME}{SYNOPSIS}
+%%
+%% Here, {...}... represents the additional category-kind arguments.  See
+%% `describe' for what all of this means.
 \def\parse@dhd#1{%  {NEXT}
   \@ifnextchar[{\parse@dhd@a{#1}}{\parse@dhd@c{#1}}}
 \def\parse@dhd@a#1[#2]#3{%  {NEXT}[MOD]{CAT}
@@ -347,6 +390,10 @@
   % {NEXT}{CAT}{{...}...}{SYNOPSIS}:NAME\q@
   #1{kwd}{#2}{#3}{#5}{#4}}
 
+%% \dhead[MOD]{CAT}{...}...[NAME]{SYNOPSIS}
+%%
+%% Typeset a description head.  Use this within the first argument of
+%% `describe*'; see `describe' for the details.
 \newif\if@dheadfirst
 \def\dhead{\parse@dhd\dhead@}
 \def\dhead@#1#2#3#4#5{%  {MOD}{CAT}{{...}...}{NAME}{SYNOPSIS}
@@ -368,6 +415,8 @@
   #5%
 }
 
+%% Main guts of a description environment.  The argument here typesets the
+%% header line(s).
 \def\desc@begin#1{%
   \let\saved@after@desc\after@desc%
   \gdef\after@desc{}%
@@ -384,12 +433,67 @@
 }
 \def\desc@end{\endlist\after@desc\global\let\after@desc\saved@after@desc}
 
-\@namedef{describe*}#1{\desc@begin{#1}}
-\expandafter\let\csname enddescribe*\endcsname\desc@end
+%% \begin{describe}[MOD]{CAT}{...}...[NAME]{SYNOPSIS}
+%%   ...
+%% \end{describe}
+%%
+%% Describe some kind of program object.  The CAT names the category of thing
+%% being described -- this will be shown in the header, and index.  The
+%% SYNOPSIS is an implicit `prog' environment in which invoking the thing can
+%% be summarized.
+%%
+%% The {...}... are any additional arguments required by the category's kind
+%% (e.g., method specializers).
+%%
+%% The NAME is the name of the thing, which ends up in the index and
+%% cross-reference label.  If omitted, it defaults to the first word of the
+%% SYNOPSIS, except that there are some special cases.
+%%
+%% The MOD is the modifier to apply.  If omitted, it will usually default to
+%% `plain', but in the absence of a NAME, some kinds of synopses are
+%% recognized specially:
+%%
+%%   * `setf (NAME ...) ...': selects NAME, and defaults MOD to `setf'.
+%%
+%%   * `*NAME*': selects NAME, without the earmuffs, and defaults MOD to
+%%     `muffs'.
+%%
+%%   * `:NAME': selects NAME, withtout the colon, and defaults MOD to `kwd'.
 \def\describe{\parse@dhd\desc@}
 \def\desc@#1#2#3#4#5{\desc@begin{\dhead@{#1}{#2}{#3}{#4}{#5}}}
 \let\enddescribe\desc@end
 
+%% \begin{describe*}
+%%     {\dhead[MOD]{CAT}{...}...[NAME]{SYNOPSIS}
+%%      ...}
+%%   ...
+%% \end{describe*}
+%%
+%% This is the fancy form of `describe' for describing several different
+%% things at once.
+\@namedef{describe*}#1{\desc@begin{#1}}
+\expandafter\let\csname enddescribe*\endcsname\desc@end
+
+%% \descref{CAT}{...}...{LABEL}[TEXT]
+%% \descref*{CAT}{...}...{LABEL}
+%%
+%% Typesets a cross-reference to a described thing.  The CAT names the
+%% category of thing being described, and the LABEL names the specific thing.
+%%
+%% The {...}... are any additional arguments required by the category's kind
+%% (e.g., method specializers).
+%%
+%% The precise rules for how the LABEL matches the name in the description
+%% depend on the description's modifier:
+%%
+%%   * `plain': the LABEL is the same as the NAME.
+%%   * `setf': the LABEL should be `setf/NAME'.
+%%   * `muffs': the LABEL should be `*NAME*', i.e., with the earmuffs
+%%     restored.
+%%   * `kwd: the LABEL should be `:NAME', i.e., with the colon restored.
+%%
+%% Usually a page-number cross-reference is included, so as to help readers
+%% of a dead-tree copy; this is suppressed by the `*' version.
 \def\descref{\@ifstar%
   {\descref@i{}\@gobble{}}%
   {\descref@i{ (}{\noexpand\autopageref}{)}}}
@@ -410,5 +514,29 @@
   \@tempa{{\code{#5}}#6#1}#3%
 }
 
+%% Description categories.
+\definedescribecategory{sym}{symbol}
+\definedescribecategory{fun}{#1{function}}
+\definedescribecategory{gf}{generic #1{function}}
+\definedescribecategory{msg}{message}
+\definedescribecategory{var}{variable}
+\definedescribecategory{modvar}{module variable}
+\definedescribecategory{const}{constant}
+\definedescribecategory{meth}[method]{primary #1{method}}
+\definedescribecategory{ar-meth}[method]{\code{:around} #1{method}}
+\definedescribecategory{be-meth}[method]{\code{:before} #1{method}}
+\definedescribecategory{af-meth}[method]{\code{:after} #1{method}}
+\definedescribecategory{cls}{class}
+\definedescribecategory{rst}{restart}
+\definedescribecategory{ty}{type}
+\definedescribecategory{mac}{#1{macro}}
+\definedescribecategory{feat}{feature macro}
+\definedescribecategory{lmac}{local #1{macro}}
+\definedescribecategory{parse}{parser spec}
+\definedescribecategory{parseform}{parser form}
+\definedescribecategory{opt}{option handler}
+\definedescribecategory{optmac}{option macro}
+\definedescribecategory{plug}{pluggable parser}
+
 %%%----- That's all, folks --------------------------------------------------
 \endinput
